This invention relates to providing a system for improved magnetization of flexible sheet material, such as magnetic rubber. More particularly, this invention relates to providing a system for magnetization of pre-printed flexible magnetic sheet material.
Flexible magnetic sheet material is customarily used in a variety of useful products ranging from refrigerator magnets to temporary signage applied to exterior metallic surfaces of transportation vehicles. In many applications, one surface of the flexible magnetic sheet material is imprinted with advertising or informational indicia. Most commercial printing processes prohibit the use of magnetized substrates due to interference with the printing process by the magnetic field of the sheet. It is therefore customary to magnetize the flexible magnetic sheet after printing has been applied.
The flexible magnetic sheet material customarily used in producing the above-described products has been relatively thick (often about 30 mil). This thickness has allowed the material to be magnetized to a usable degree by exposure of the unprinted side of the flexible magnetic sheet material to a magnetic field. The use of thinner more cost-effective sheet materials (thicknesses below about 15 mil), has been limited by the lack of effective post-printing magnetization processes. A system allowing a thinner (pre-printed) flexible magnetic sheet material to be magnetized to levels nearing those of conventional flexible magnetic sheet materials would be of great benefit to many.